One of the most important factors contributing to the effective use of a computer is the interface between the computer and a person using it. Unquestionably the most popular computer interface device is the keyboard, which has a plurality of depressable keys each corresponding to a particular alphanumeric character, symbol, or computer function. While computer keyboards are widely accepted and quite suitable in many situations, keyboards are not always the most efficient, convenient, or easy to use devices.
For example, on a typical desktop the most commonly used space is that space closest to the edge near the user who is sitting at the desk. Computer keyboards must occupy a considerable amount of this space on the desktop in order to remain within easy reach of the user. However, with a computer keyboard occupying this space, very little space is left to spread-out papers, write by hand, or the like. To overcome this drawback there are several keyboard holders that slide out of the way when the user is not using the keyboard. But such devices make it difficult to slide the keyboard back out into a useful position if the immediate workspace has since been occupied by papers, a coffee cup, or the like. Such devices are somewhat cumbersome to use.
Another drawback of computer keyboards is that they include up to 110 individually marked keys mounted to a base with as many switches. All of these components must be produced and assembled, which accounts for considerable expense. Keyboards are relatively expensive to manufacture, and since they are mechanical, are also more prone to failure than solid state devices. Further, the conventional keyboard cannot be quickly changed to a new keyboard layout, such as might be desired by those who have learned a keyboard layout other than the somewhat inefficient but traditional QWERTY layout.
Still another drawback of computer keyboards is that they are built generally in one size for all users. As a result, users with relatively small or large hands must adapt to a keyboard size that is not optimal for their particular hand size. A person with smaller hands must stretch further to strike a key some distance from a home row of keys, whereas a person with larger hands will have a harder time accurately striking any desired key. Keyboard size that is optimized for a particular use may lead to decreased hand fatigue. However, keyboard manufacturers have determined an ergonomically acceptable compromise, which is a compromise nevertheless.
Still another drawback of the conventional computer keyboard is that it requires the user to type with his hands close together in an unnatural manner. It has been found that so called "split" keyboards, which are split into a separate keyboard for each hand, are more comfortable for the user and produce a slightly faster typing speed as a result. However, such keyboards are generally more expensive and as such have not gained widespread popularity.
Many pocket-sized and portable computers are available with miniature keyboards. Typing on these miniature keyboards using proper typing form is nearly impossible, especially for people with average or large sized hands. As such, keyboards have, to a large extent, determined the smallest usable size for small and portable personal computers. As computers become smaller and smaller, keyboards, it would appear, must be abandoned for pen or stylus based input screens that recognize the user's handwriting or printing. However, many people can type much faster than they can write by hand, so such stylus-based input screens are often not preferable to a conventionally sized keyboard, even if a smaller computer is more portable and convenient.
Pointing devices, such as "mouse" pointing devices and so called "track ball" devices are also popular computer interfaces. Generally, these types of devices provide velocity information, in both an X direction and an orthogonal Y direction, to the computer, as well as signals from one or more momentary contact push buttons. A pointing icon or other "tool" on a computer monitor responds to such velocity input by corresponding X and Y movement on the computer monitor. Graphics tablets are another type of "pointing" input device that provide the computer with X and Y positional information, as opposed to velocity information, which is used in much the same manner by the computer. Such devices are well suited for pointing to various software "push button" options on the screen, selecting portions of text or a group of software "objects," freehand on-screen drawing, positioning a typing cursor location, and similar functions. However, such pointing devices are remarkably ill-suited for text data input.
Another type of computer interface device which is not yet in widespread use is a voice-activated interface device. In such a device, spoken commands and data are interpreted by the computer. The hardware required for such a device is relatively simple, typically just a microphone and an interface circuit. Microphones take very little space, and thus free-up a considerable amount of desk space. However, such an input device is not well suited for pointing operations, and therefore a mouse or other pointing device is still typically necessary. Further, such devices currently are somewhat frustrating to use since they require sophisticated interpretive software that, as of yet, does not always accurately interpret spoken words. While the accurate interpretation of spoken words by computers is imminent, one does not always wish to vocalize the data being entered into the computer. For instance, often people enter sensitive and private information into their computer while speaking to a customer or client on the phone, or with other people nearby. Moreover, with many people speaking to their computers in the same room, a high level of noise results. In a library or other relatively quiet environment, vocalizing information to a computer is inappropriate and undesirable.
Other types of computer interfaces have been developed to overcome some of the above mentioned drawbacks. For example, U.S. Pat. No. 5,212,372 to Quick et al. on May 18, 1993, teaches a glove device that has sensors for measuring the curvature of each finger at joints thereof. For entering numerical data, a person using this type of device curves his fingers to point to "zones," or virtual keys, that each represent a particular number. While the input of alphabetical data is mentioned in the Quick disclosure, only numerical zones are illustrated and it remains unclear how such a device could possibly be used to enter the twenty-six additional characters of the alphabet, especially since the little finger is used solely for designating an "enter" key and is therefore not available for pointing to alphanumeric zones.
A variety of similar glove-based prior art devices exist, and in most cases each uses some type of joint flexing sensor to determine finger curvature. Many such devices are designed for communication with deaf or otherwise challenged individuals, and typically provide for computer interpretation of alphanumeric data formed by a single hand with standard sign language. It is a slow and fatiguing process for people, even those fluent in sign language, to use such devices to enter a large amount of data into a computer, such as might be required while typing a patent disclosure, for example. Further, while finger curvature is relatively easy to detect in a variety of sophisticated ways, such detection is only accomplished in one dimension. Lateral movement of the finger, for example from the "J" key to the "H" key of a standard QWERTY keyboard, cannot be detected by such joint flexure sensors as disclosed in the prior art. This drawback is also evident in many "virtual reality" data manipulation gloves, which also include a variety of motion sensors on similar gloves. As a result, such devices have limited use and are not well suited for prolonged data entry from a wide selection of character and command keys, such as those found on the standard computer keyboard.
It is clear, then, given the above drawbacks associated with current man to computer interface devices, that a device that overcomes these drawbacks is strongly needed. Such a needed device would be adaptable to any individual, regardless of hand size or typing style. Further, such a needed device could be used equally well for both alphanumeric data entry, command entry, and X,Y pointer input. Still further, such a needed device would take up no additional space on a person's desktop, could be used over papers on a desk, and could be easily used with computers of any physical size. Indeed, a needed device of this type would be as portable as the smallest pocketbook computers, and would not require the user's hands to be held close together as with the conventional keyboard. Such a needed device would be to a large extent software re-configurable, making use of the device immensely flexible and adaptable. The present invention fulfills these needs and provides further related advantages.